#!/usr/local/bin/node

var sys = require("sys");

if ( process.argv.length < 2 || process.argv[2] == "-h" || process.argv[2] == "--help")
{
    sys.print("Usage: json [<json-function>]\n")
    process.exit(1);
}

var script = process.argv[2] || "return v;";

var fn = new Function("v", "sys",  script);

var stdin = process.openStdin();
stdin.setEncoding('utf8');
var stdInBuf=[];
stdin.addListener('data', function (chunk) { stdInBuf.push(chunk) });
stdin.addListener('end', function()
{
    var data = JSON.parse(stdInBuf.join(""));
    
    var result = fn.call(data, data, sys);
    
    if (typeof result == "string")
    {
        sys.print(result);
    }
    else
    {
        sys.print(JSON.stringify(result, undefined, 4) + "\n");
    }
});